JPH03260789A - Counter for paper or the like - Google Patents

Abstract

PURPOSE:To accurately locate a rotor fast by performing servo control so that a driving force is obtained toward a fixed position. CONSTITUTION:This counter is equipped with a locating command means 1, a rotor position detecting means 2, a rotor rotating speed detecting means 3, a servo control means 4, and a rotor driving means 5. When a locating command is generated, the driving force is so applied as to reverse the rotor and the servo control is performed to reduce the speed of the rotor rotation according to position information on the rotating rotor obtained from the rotor position detecting means and speed information on the rotor obtained by the rotor speed detecting means 3. Consequently, the rotor is not stopped by detecting the fixed position, but brought under the servo control so as to obtain the driving force toward the fixed position, so the rotor 6 can be stopped speedily at the fixed position.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a paper sheet counting machine that automatically counts paper sheets such as banknotes.

[Conventional technology]

A paper sheet counting machine that sequentially attracts and separates paper sheets one by one and counts them by rotating a plurality of suction shafts installed on a rotor that rotates a bundle of paper sheets, such as a bundle of banknotes, loaded in a holder. is widely used.

In such a paper sheet counting machine, when starting counting,
The suction hole provided on the outer surface of the suction shaft must face the surface of the paper sheet. This is because the suction hole of the suction shaft faces the surface of the first sheet of paper and suctions that sheet, resulting in the sheets coming into close contact with each other, and the internal pressure of the suction shaft reaches a predetermined suction pressure (vacuum pressure). This is because when the vacuum switch detects that the vacuum switch has reached ( ), the rotor on which the suction shaft is disposed is rotated (normally rotated) and the counting operation is started.

If the suction hole of the suction shaft does not face the sheet surface, the first sheet cannot be picked up, and therefore the pressure inside the suction shaft does not reach the specified value. This means that the vacuum switch will not operate and counting will not start.

Therefore, at the start of counting, the suction shaft should be positioned so that the suction hole of the suction shaft is at a position facing the surface of the paper sheet, that is, at a position where the paper sheet can be sucked (hereinafter referred to as the "fixed position"). must be positioned. There are multiple suction shafts (
Since the suction shafts (usually five) are arranged on the rotor so as to rotate mechanically in conjunction with the rotation of the rotor, it is necessary to position the rotor so that one of the suction shafts is in a fixed position.

Various methods have been proposed for this rotor positioning method.

The simplest mechanism is a mechanical stopping mechanism in which a stopper or the like is engaged with a locking groove provided on the circumferential surface of the rotor. Although this method ensures reliable stopping, it has the disadvantage of making a loud mechanical stop noise.

Next, the rotor is reversely rotated at low speed when counting starts, and the low-speed reverse rotation of the rotor is stopped when the fixed position detection means detects that the fixed position indicating member provided on the circumferential surface of the rotor has reached the fixed position. There are some devices in which the suction shaft is positioned at a fixed position.
There is one described in Publication No. 17. With this method, it is possible to stop the rotor in a non-contact manner without using any mechanical stopping mechanism.

[Problem to be solved by the invention]

However, since this method does not use any locking parts such as stoppers to stop the rotor, the rotor continues to rotate due to inertia even after the rotor drive motor has stopped driving.
It may happen that it passes through the fixed position (overrun). Further, even if the brake is electrically applied at the time when the home position detecting means detects the home position, some overrun may occur and the problem is poor. In order to prevent this, the reversal speed must be reduced to an extremely low speed that does not cause overrun. For this reason, there was a problem in that it took a long time to locate the device in a fixed position, making it impractical.

The present invention has been made to solve these problems, and an object of the present invention is to provide a sheet counting machine that can quickly and reliably set the suction shaft to a fixed position.

[Means to solve the problem]

According to the present invention, after the rotor is positioned at a fixed position where the suction hole of the rotating suction shaft provided on the upper surface of the rotating rotor faces the sheet surface of the sheet bundle loaded in the holder. , a paper sheet counting machine that sequentially suctions and separates paper sheets one by one using the suction shaft to start counting =1, a fixed positioning command means for commanding the positioning of the suction shaft to a fixed position;
rotor position detection means for detecting the position of the rotor; rotor speed detection means for detecting the rotational speed of the rotor;
The rotor is rotated so that the rotor is reversed at high speed based on the t11 force of the fixed position command means, and the suction shaft is stopped at the fixed position based on the output of the rotor position detection means and the output of the rotor speed detection means. The invention is characterized by comprising a servo control means for performing servo control to decelerate the rotation of the motor.

[For production]

In the paper sheet counting machine of the present invention, when a fixed positioning command is given, a driving force is applied to rotate the rotor in a high-speed reverse direction, and the position information of the rotating rotor obtained from the rotor position detection means and the rotor speed detection means are Servo control is performed to decelerate the rotation of the rotor based on the rotor speed information obtained.

Therefore, instead of detecting and stopping the rotor at a fixed position, servo control is performed so that driving force is obtained toward the fixed position, so that the rotor can be quickly stopped at the fixed position.

〔Example〕

Hereinafter, embodiments of the paper sheet counter according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing a schematic configuration of a paper sheet counter according to the present invention.

A fixed positioning command means 1 for commanding fixed positioning, a rotor position detecting means 2 for detecting the rotor position, and a rotor rotational speed detecting means 3 for detecting the rotational speed of the rotor are provided, and each output of these is controlled by servo control. The output thereof is supplied to a rotor drive means 5 such as a servo motor that drives the rotor 6.

FIG. 2 is a plan view showing the specific structure of the mechanical section of the paper sheet counter according to the present invention.

A holding plate 12 is provided to set the bundle of paper sheets 11 at the time of counting, and this holding plate 12 is at the position 12' shown by the dashed line before counting starts, and at the time of counting, it is moved to the guide 14 to the position shown by the solid line. The sheet bundle 11 is pressed against the holding rod 13 by rotating along the holding rod 13.

At this time, a suction surface 16a of a suction shaft 16, which will be described later, is in contact with the surface of the bundle of paper sheets 11. The guide 14 is provided with a sensor 15 as an insertion detection means such as a photo sensor or a microswitch that detects the set of paper sheets 11 by detecting the movement of a detection piece.

Usually, five suction shafts 16 are provided on the rotor 17, and they rotate counterclockwise in conjunction with the counterclockwise rotation (normal rotation) of the rotor 17, and also rotate in the rotational direction. It looks like this. In other words, it rotates while revolving. The rotor 17 is rotated by the rotation of the rotor motor 18 via a pulley 19 and a belt 20. The rotor motor 18 is a servo motor, and a rotary encoder 21 for servo control is attached to its rotating shaft, and as it rotates, it generates human-phase and B-phase pulse signals containing direction information. .

Five detection pieces 22 are protruded on the outer peripheral surface of the rotor 17 in correspondence with the suction shaft, and when the detection pieces 22 pass a control start sensor 23 which also serves as a counting sensor, a pulse signal is sent from this sensor. occurs. This control start sensor 23 is composed of a photo ink rubber, a proximity switch, or the like.

FIG. 3 is a front view showing the suction surface 16a of the suction shaft 16, and it can be seen that the suction surface 16a is provided with a large number of suction holes 16b. Since the inside of this suction bow shaft 16 is under negative pressure by a vacuum pump or the like, air is sucked through the suction hole 16b, and nearby objects are attracted.

FIG. 4 is a block diagram showing details of the control section in the paper sheet counter of the present invention.

The rotary encoder 21 attached to the servo motor 18 outputs two signals, A phase and B phase, as the servo motor rotates.
Different types of pulses are output and input to the pulse discriminator 31. This pulse discriminator 31 has a phase shift A
It inputs phase and B-phase pulses to discriminate the rotational direction of the low reencoder 21, and outputs pulses for each rotational direction, and is well-known, so detailed configuration will be omitted. The reverse direction output and the forward direction output E of the pulse discriminator 31 are input to the down input terminal and up input terminal of the up/down counter 32, respectively. Further, the up/down counter 32 is set with a predetermined value that defines the stop position and reverse rotation torque, which is preset with a numerical value setter 33 such as a dip switch. The count is increased or decreased. Note that the range of the digital value output from the up/down counter 32 is, for example, 0 to 255. This counter 32
The output of is given to the D/A converter 34, and this D/A
For example, when the input value is 0, the converter 34 converts i;
+10V, 128 (7) when 0v1255 -10
Outputs the analog voltage value of V. Then, a difference signal G between the output signal F of this D/A converter and the output of the D/A converter 34 is passed through a differentiating circuit 35 consisting of a resistor and a capacitor, and a difference signal G is given to a drive circuit 36, which drives the servo motor. 18 is driven to rotate.

Note that the drive circuit 36 is provided with feedback for drive current control. Further, the differentiating circuit 35 operates to detect the rotational speed by differentiating the position signal of the rotor 17, and as described later, the differential circuit 35 operates to detect the rotation speed by differentiating the position signal of the rotor 17. This is what we are trying to add.

In addition, the load (L) of the up/down counter 32 mentioned above is
The D) terminal is provided with the Q output of a D-type flip-flop 37, which uses the output B of the control start sensor as a clock input and the fixed positioning command signal A as a clear (CLR) input.

Note that the rotary encoder 21, pulse discriminator 31, up/down counter 32, etc. constitute rotor position detection means.

Hereinafter, with reference to the block diagram in FIG. 4, the waveform diagram in FIGS. 5 and 6, the flowchart in FIG. The operation of several devices will be explained.

First, when the banknote bundle 11 is inserted into the holder 12, the insertion detection means 15 detects this, and closes the holder 12 based on a low-level holder close command output from a control section (not shown) to close the banknote bundle 11. Place it in the number one position. At this time, as shown in FIG. 8(a), it is assumed here that the detection piece 22 of the rotor 17 is located at a position away from the control start sensor 23. First, the schematic control operation is shown in Fig. 7(a).
Since the holder closing command described above also serves as the fixed positioning command A (A in FIGS. 4 to 6), the generation of this fixed positioning command (step 5101) causes the servo motor 18 to is commanded to perform a high-speed reversal (step 510).
2) When it is detected that the detection piece 22 provided on the rotor 17 has passed the control start sensor 23 which also serves as a 51-number sensor (step 8103), the servo is activated based on the rotor position information and speed information. Control is then terminated (step 5104).

FIG. 7(b) is a flowchart 1 which describes the flow of FIG. 7(a) in more detail.

When the fixed positioning command A is generated (step 5201),
Since this signal is a low level signal, the D-type flip-flop 37 is cleared by this fixed positioning command.
The Q output signal C becomes low level. Since this low level signal C is given to the load terminal of the up/down counter 32, a predetermined value, for example 224, set in advance by the numerical value setter 33 is loaded (step 5202
), the output Q of the up/down counter 32 is set to a predetermined value 224.
is output. This value is converted into an analog voltage signal F by the D/A converter 34, and a driving force (G) for reversing the rotor 17 at high speed is obtained.

The D/A converter 34 has the human output relationship as described above, and when commanding a fixed position, the D/A converter 34 outputs 224
becomes the output value of the up/down counter 32, a driving force is applied to the drive circuit 36, and the rotor motor 18 starts high-speed reverse rotation to position the suction shaft 16 at the normal position (step 8203). When high-speed reversal is started, the rotary encoder 21 attached to the rotating shaft of the rotor motor 18 outputs 2Fffl pulses of A phase and B phase, which are input to the pulse discriminator 31.

The pulse discriminator 31 inputs phase-shifted A-phase and B-phase pulses to discriminate the rotational direction of the rotary encoder 21.

and outputs pulses for each direction of rotation.

As can be easily seen from FIG. 8(a), the time until servo control is started differs depending on the angle α formed between the detection piece 22 and the control start sensor 23 in the initial state.

Since the rotation is currently in reverse, the pulse D is output only from the opposite direction terminal of the pulse discriminator 31 based on the A-phase and B-phase pulses, and a signal is manually input to the up-down counter 32 only on the down side. At this time, since the low level signal C is still input to the load terminal LD of the up/down counter 32 and the load state continues, the down input and up/down input are ignored, and the Q of the up/down counter 32 is ignored.
The output does not change even when reversal is initiated. Therefore, the voltage F of the D/A converter is constant at -7.5V and there is no change in value, so no output is generated from the differentiating circuit 35, and the torque control signal G of the drive circuit 36 remains at 7.5V. There is no change.

As the rotor 17 continues to rotate in reverse, the detection piece 22 provided on the circumferential surface of the rotor reaches the control start sensor 23, as shown in FIG. 8(b). As described above, the reversal speed at this point differs depending on the angle α formed between the detection piece 22 and the control start sensor 23. This control start sensor 23
The passage of is seen as L, and when the detection piece 22 completely passes the control start sensor 23 (step 5204), the output B of the control start sensor 23 rises, and at this rise, the output B of the control start sensor 23 rises.
The Q output C of the type flip-flop '37 becomes high level and the load command to the up/down counter 32 is stopped. Therefore, from this point on, the down force or up force E from the pulse discriminator 31 becomes valid (step 5205), and the output Q of the up/down counter 32 starts to change.

Therefore, a driving force is generated according to the counter value.

If it takes a long time for the detection piece 22 to pass through the control start sensor 23 after the command to position is issued (FIG. 5), -7 is sent to the drive circuit 36 as a torque control signal.
, 5V is applied for a long time, the rotor 17 reverses to a sufficiently high speed, and after the detection piece 22 has completely passed through the control start sensor 23, a pulse is output from the terminal in the opposite direction of the pulse discriminator 31. The value of the output Q of the up/down counter 32 rapidly decreases from 224 due to the down input at high speed.

Along with this, the voltage as the driving force from the D/A converter 34 also rises rapidly from -7.5■, approaches OV, and the driving force for reverse rotation itself decreases, while the voltage from the D/A converter 34 Due to the rapid change in the output, an output corresponding to the amount of change is applied from the differentiating circuit 35 as a reverse driving force (step 5206). As a result, as shown in FIG. 5, normal rotation torque is generated in the torque control signal G, and the rotor motor attempts to rotate in the normal direction. As a result, the reverse speed rapidly decreases, and the rate at which the output value of the up/down counter 32 decreases also decreases. Therefore, the output of the differentiating circuit is approximately O
Since the torque control signal C corresponds to the position signal (driving force) which is the output signal F of the D/A converter, the reverse rotation speed decreases and the up/down counter 32
When the value reaches the final target value of 128, the rotor motor 18 will stop (step 5207).

This state is shown in FIG. 8(c), where the detection piece 22 stops at a position rotated by a certain value, for example, an angle β corresponding to 96 pulses, after passing the control start sensor 23. There is.

Note that in some cases, a slight overrun may occur. This is the last pulse of D in Figure 5.
When an overrun occurs and the count value of the up/down counter 32 passes, for example, 128 and reaches 127, the analog voltage of the D/A converter changes to positive, generating forward rotation torque, and the rotary encoder 21 becomes positive. Then, one pulse is inputted from the positive terminal of the pulse discriminator 31 (the pulse shown in E in FIG. 5), and the value of the up/down counter 32 becomes 128, and the rotor motor 1
8 stops.

FIG. 5 shows a case where, when the fixed positioning command signal A is given, the detection shaft 22 of the rotor 17 has already been applied to the control start sensor 23, and the signal B has been output. In this case, the detection piece 22 completely passes the control start sensor 23 immediately after the rotor 17 starts rotating due to the driving force applied to the rotor 17 in order to reverse the rotation at high speed in the process described above. The speed has not reached a large value yet. For this reason, the reverse pulse D from the rotary encoder 21 is input down at a slightly low speed, and the value of the output Q of the up/down counter 32 does not decrease rapidly from 224, and the output of the differentiating circuit 35 is hardly obtained. /
The voltage F of the A converter 34 is approximately given as the torque control signal G, and the rotor immediately stops at a position rotated by 96 pulses from the control start sensor 23.

The numerical value to be preset in the up/down counter 32 is 224 in the above-mentioned embodiment. It can be obtained by inversely calculating the number of pulses of the rotary encoder 2]. That is, the load value may be determined by calculating backwards so that the counter value becomes 128 at the home position.

When the positioning is completed as described above, the surface of the first banknote is exactly facing the suction hole 16b of the suction shaft 16, and the suction pressure inside the suction shaft 16 is increased by attracting the banknote. When the value exceeds a predetermined value, the vacuum switch is turned on and rotor 1
7 rotates forward at high speed and performs counting operations while adsorbing and separating. Counting is performed by counting the signals obtained each time the detection piece 22 of the rotor passes the control start sensor 23 when the vacuum switch is engaged.

Note that a pressure sensor may be used instead of the vacuum switch. Further, the driving force for high-speed forward rotation during counting is switched and applied to the motor by another circuit (not shown).

In the embodiments described above, positioning was performed at the start of counting, but it may also be performed at the end of counting.

Note that the holder may be closed and reversed at the same time.
Alternatively, when the holder is closed, the closing of the holder may be separately detected and the detection output may be used as a command to move to a fixed position to perform the reverse rotation.

Alternatively, the rotor may be reversed by a counting start signal generated by manual operation of a separately provided switch.

Further, although the rotor speed is detected based on the change in the output of the position detecting means, the rotor speed detecting means may be provided separately.

In addition, by using a detection piece on the rotor circumferential surface, a separate position detection sensor is provided that detects when the suction shaft is at the specified position, and when a command is issued to move the suction shaft to the specified position, the above-mentioned Reverse servo control may also be performed. Although the servo control is performed using the hardware configuration shown in FIG. 4, the servo control may be performed using software.

Furthermore, the present invention can be applied to a banknote counting machine having a function of detecting different denominations, and as a result, the rotor can be positioned in a fixed position extremely accurately, thereby increasing the accuracy of identifying the first banknote.

〔Effect of the invention〕

As described above, according to the present invention, since servo control is performed so that driving force is obtained toward the home position, it is possible to perform home positioning extremely quickly and accurately. In addition, if the counting sensor is also used as a servo control start signal generating means for positioning, the number of sensors can be reduced.
The structure can be simplified.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a schematic configuration of a paper sheet counter according to the present invention, Fig. 2 is a plan view of the paper sheet counter, and Fig. 3 is a front view showing the suction surface a of the suction shaft. , FIG. 4 is a block diagram showing the configuration of a control device for servo control of the rotor, and FIG.
The figure is a waveform diagram for fixed positioning when the rotor rotates a lot.
FIG. 6 is a waveform diagram for positioning when the rotor rotation amount is small, FIG. 7(a) is a schematic operation flowchart of the device of the present invention, FIG. 7(b) is a detailed operation flowchart, and FIG. 8 is a waveform diagram of the rotor. FIG. DESCRIPTION OF SYMBOLS 1... Fixed positioning command means, 2... Rotor position detection means, 3... Rotor speed detection means, 4... Servo control means, 5... Rotor drive means, 6... Rotor, 1
DESCRIPTION OF SYMBOLS 1... Banknote bundle, 12... Holding plate, 16... Suction shaft,
17... Rotor, 18... Servo motor, 21...
- Rotary encoder, 22... Detection piece, 23... Control start sensor, 31... Pulse discriminator, 32... Up/down counter, 33... Numeric value setter, 34...
・D/A converter, 35... Differential circuit, 36...
Drive circuit, 37...D type flip-flop

Claims (1)

[Claims] 1. The rotor is positioned at a fixed position where the suction hole of the rotating suction shaft provided on the upper surface of the rotor faces the sheet surface of the sheet bundle loaded in the holder. After that, the paper sheet counting machine starts counting by suctioning and separating the paper sheets one by one using the suction shaft, and a fixed position command means for commanding the positioning of the suction shaft to a fixed position; rotor position detection means for detecting the position of the rotor; rotor speed detection means for detecting the rotational speed of the rotor; and rotating the rotor at high speed in reverse based on the output of the fixed positioning command means, and the output of the rotor position detection means. and servo control means for performing servo control to decelerate the rotation of the rotor so that the suction shaft stops at a fixed position based on the output of the rotor speed detection means. . 2. The paper sheet counter according to claim 1, wherein the rotor speed detection means is a differential circuit that detects the speed based on a change in the output value of the rotor position detection means. 3. Further comprising a control start detection means for detecting a control start point after high-speed reversal of the rotor, and the servo control means starts the servo control in response to a control start point detection signal from the control start detection means. The paper sheet counting machine according to claim 1, characterized in that: